US2005008287A describes a modular dispersion compensator to compensate for dispersion of a WDM optical signal. The method begins by directing a WDM optical signal having a prescribed bandwidth to a first dispersion compensating element and substantially compensating, with the first dispersion compensating element, each wavelength in the WDM optical signal for dispersion at a prescribed wavelength within a first sub-band of the prescribed bandwidth. The method continues by directing to a second dispersion compensating element wavelengths received from the first dispersion compensating element outside the first sub-band and substantially compensating, with the second dispersion compensating element, each wavelength received from the first dispersion compensating element for dispersion at a prescribed wavelength within a second sub-band of the prescribed bandwidth. The wavelengths received from the second dispersion compensating element are combined within the second sub-band of the prescribed bandwidth with the wavelengths received from the first dispersion compensating element within the first sub-band.
US2004208619A discloses a Re-Configurable Dispersion Compensation Module (RDCM). The RDCM combines existing optical switch technology with existing fixed DCM technology and advantageously also with existing TDCM (Tunable Dispersion Compensation Module) technology into a programmable smart optical component. Advantageously Micro-Electrical Mechanical Switch (MEMS) optical switch technology may be used. The alternate RDCM technology provides a controller, and a set of controllable switches to employ a set of DCMs and TDCMs for adjusting the dispersion compensation along an optical signal path. This alternate RDCM technology mitigates the problems of conventional TDCMs, while fitting most of the requirements for high speed systems, and being of a compact size.